DLG2 and Anxiety: To investigate psychiatric endophenotypes associated with DLG2 haploinsufficiency (and concomitant PSD‐93 protein reduction) a novel clinically relevant Dlg2+/− rat was assessed for abnormalities in anxiety, sensorimotor gating, hedonic reactions, social behaviour, and locomotor response to the N‐Methyl‐D‐aspartic acid receptor antagonist phencyclidine.